Resin compositions

Abstract

Silica fume subject to a mechanical reduction in size by a milling process such as a fluid energy mill or jet mill is disclosed. The overall size reduction is at least 10%. The milled silica fume product should have not more than 0.5% by weight unable to pass through a 325 mesh screen. The milled silica fume can be used in thermoplastic resins, cementitious material and refactory material. The use of the milled silica fume with UPVC or PVC to make conduit with improved elastic modulus, improved impact resistance, decreased wall thickness and increased calcium carbonate content is specifically disclosed.

What is claimed is: 
     
       1. An artifact made from a thermoplastic resin composition said thermoplastic resin composition containing as an essential ingredient therein silica fume which has been subjected to a fluid energy milling process whereby unmilled silica fume is reduced in size to produce said silica fume. 
     
     
       2. The artifact of claim 1 wherein the milled silica fume is coated. 
     
     
       3. The artifact of claim 1 wherein the milled silica fume has had an overall size reduction of at least about 10% as compared to unmilled silica fume. 
     
     
       4. The artifact of claim 1 wherein no more than about 0.5% by weight of milled silica fume is unable to pass through a 325 mesh screen. 
     
     
       5. The artifact of claim 1 wherein the milled silica fume has had a mean particle size reduction of about 10% as compared to unmilled fume. 
     
     
       6. The artifact of claim 1 wherein the milled silica fume has had an increase in weight percent of silica fume less than about 1 micron of about 10% as compared to unmilled silica fume. 
     
     
       7. A thermoplastic resin composition suitable for extrusion of a conduit containing about 100 phr resin, up to about 4 phr thermal stabilizer, up to about 5 phr lubricant, up to about 12 phr pigment, up to about 100 phr filler and about 0.5 to 40 phr silica fume which has been subjected to a fluid energy miling process whereby unmilled silica fume is reduced in size to produce said silica fume. 
     
     
       8. A method for making an artifact from a thermoplastic resin composition comprising extruding a thermoplastic resin containing as an essential ingredient therein silica fume that has been subjected to a fluid energy milling process whereby unmilled silica fume is reduced in size to produce said silica fume. 
     
     
       9. The method of claim 8 wherein the milled silica fume is coated. 
     
     
       10. The method of claim 8 wherein the milled silica fume has had an overall size reduction of at least about 10%. 
     
     
       11. The method of claim 8 wherein the milled silica fume has no more than about 0.5% by weight of milled silica is unable to pass through a 325 mesh screen. 
     
     
       12. The artifact of claim 8 wherein the milled silica fume has had a mean particle size reduction of about 10% as compared to unmilled fume. 
     
     
       13. The artifact of claim 8 wherein the milled silica fume has had an increase in weight percent of silica fume less than about 1 micron of about 10% as compared to unmilled silica fume. 
     
     
       14. A method for making a conduit from a thermoplastic resin comprising extruding a composition containing about 100 phr of resin, up to about 4 phr thermal stabilizer, up to about 5 phr lubricant, up to about 12 phr pigment, up to about 100 phr filler and about 0.5 to 40 phr coated silica fume which has been subjected to a fluid energy milling process whereby unmilled silica fume is reduced in size to produce said silica fume. 
     
     
       15. A conduit made from a thermoplastic resin and containing as an essential ingredient therein silica fume which has been subjected to a fluid energy miling process whereby unmilled silica fume is reduced in size to produce said silica fume. 
     
     
       16. The conduit of claim 15 wherein the milled silica fume is coated. 
     
     
       17. The conduit of claim 15 wherein the milled silica fume has had an overall size reduction of at least about 10%. 
     
     
       18. The conduit of claim 15 wherein the milled silica fume is unable to pass through a 325 mesh screen. 
     
     
       19. The artifact of claim 15 wherein the milled silica fume has had a mean particle size reduction of about 10% as compared to unmilled fume. 
     
     
       20. The artifact of claim 15 wherein the milled silica fume has had an increase in weight percent of silica fume less than about 1 micron of about 10% as compared to unmilled silica fume. 
     
     
       21. A conduit made from a thermoplstic resin composition comprising about 100 phr of a thermoplastic resin, up to about 4 phr thermal stabilizer, up to about 5 phr lubricant, up to about 12 phr pigment, up to about 100 phr filler and about 0.5 to 40 phr coated silica fume which has been subjected to a fluid energy milling process whereby unmilled silica fume is reduced in size to produce said silica fume. 
     
     
       22. An artifact made from a thermoplastic resin composition, said thermoplastic resin composition containing as an essential ingredient therein silica fume which has been subject to a fluid energy milling process whereby said silica fume had an overall size reduction of at least about 10% as compared to non-reduced silica fume.